h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

To make a Baking soda bomb you will need:

1. About two teaspoons' of said soda.
2. Some vinegar
3. A small, tight container (preforably one such as found in 'Kinder Suprise' eggs - far more enjoyable than the toy itself).

It's then quite simple. Put the baking soda into one half of the plastic egg thingy. Put vinegar in the other half. Quickly shove the two together (firmly) and THROW IT AWAY - FAST.
It then explodes all over the place. If left to dry, the potent mixture will harden - crystalise - into a hard white shell. Keep away from your eyes or cuts.

Wow! That Sounds great. I think I will check that one out. Thanks

In the lunchroom at my high school, the salt and peper came in an aluminum shaker with a screw lid. They were about the size of a coffee mug. I used to enjoy making baking soda bombs in them by dumping out the salt or peper, putting in a baggie that contained a few spoons of baking soda and the vinegar in an open prescription bottle. After the baggie was carefully inserted so the vinegar remained upright and a little of the salt or pepper was replaced, it was returned to a table ready for a sucker to invert it and begin the reaction. Great fun!

Man, that's a sneaky thing to do - I'd love to see that.
An even better container, if you can find one, is a tube from a specific product. My mum buys these soluable vitamin C tablets that come in a air-tight tube with a really thick lid which prevents moisture getting in (because the tablets would bein to disolve in the pot!). Filling one of those babys with the concoction was very explosive, because the pressure really had a chance to build up before it could blow the lid off.
"Pffffffff... POP! Gurgle, and splat".